Hairstyling products such as hairsprays are used for achieving different hairstyles and for holding hair strands in place for a period of time. Typically, hairsprays comprise film-forming polymers, which when applied to keratin-containing fibres, such as human hair, form fibre-fibre welds. These welds ‘glue’ the fibres together and hence impart hold to the hairstyle.
Aerosol hairspray products usually comprise a pressure-resistant container, a nozzle, a propellant, and a hairstyling formulation. A hairspray composition is normally ejected from such products via aerosol-forming nozzle. See, for example, US2009/0104138A1. Commonly used propellants include the volatile organic compounds (VOCs) propane, butane, 1,1-difluoroethane, and dimethylether. However, VOCs are known to react with certain nitrogenic oxides, which in turn may result in the formation of ground-level ozone—a potential source of health problems. Alcohols are also often used in the hairstyling formulation, for example to reduce surface tension. However, a high proportion of alcohol may leave the hair feeling dry and brittle and some alcohols may cause an allergic response in some users. Also, ethanol is flammable and is a VOC.
There is a constant need, therefore, for more environmentally friendly, more sustainable, and affordable hairspray products, in particular for aerosol hairspray products comprising low levels of VOC and alcohol. However, altering one or more features of an aerosol hairspray product can be challenging since the interrelationship therebetween affects the product performance. For example, utilising a different propellant may result in an unacceptable droplet size of the ejected composition and consequently unsatisfactory hold. Furthermore, certain hairstyling polymers may be incompatible with hairspray products comprising low levels of VOC and/or alcohol.
When considering the aforementioned needs, therefore, good hairspray performance should be maintained. Performance benefits may include, for example: excellent hold; long-lasting hold; good humidity resistance; shapeable hold; acceptable drying time; excellent soft, natural hair feel; acceptable and/or non-stickiness/tackiness of the hands and hair. Of particular relevance to consumers is natural hair feel and non-tackiness of the hands and hair.